mpd/src/playerData.c

/* the Music Player Daemon (MPD)
 * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
 * This project's homepage is: http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "playerData.h"
#include "conf.h"
#include "log.h"
#include "os_compat.h"

int buffered_before_play;
int buffered_chunks;

#define DEFAULT_BUFFER_SIZE         2048
#define DEFAULT_BUFFER_BEFORE_PLAY  10

static PlayerData *playerData_pd;

void initPlayerData(void)
{
	float perc = DEFAULT_BUFFER_BEFORE_PLAY;
	char *test;
	int shmid;
	int crossfade = 0;
	size_t bufferSize = DEFAULT_BUFFER_SIZE;
	size_t allocationSize;
	OutputBuffer *buffer;
	ConfigParam *param;
	size_t device_array_size = audio_device_count() * sizeof(mpd_sint8);

	param = getConfigParam(CONF_AUDIO_BUFFER_SIZE);

	if (param) {
		bufferSize = strtol(param->value, &test, 10);
		if (*test != '\0' || bufferSize <= 0) {
			FATAL("buffer size \"%s\" is not a positive integer, "
			      "line %i\n", param->value, param->line);
		}
	}

	bufferSize *= 1024;

	buffered_chunks = bufferSize / CHUNK_SIZE;

	if (buffered_chunks >= 1 << 15) {
		FATAL("buffer size \"%li\" is too big\n", (long)bufferSize);
	}

	param = getConfigParam(CONF_BUFFER_BEFORE_PLAY);

	if (param) {
		perc = strtod(param->value, &test);
		if (*test != '%' || perc < 0 || perc > 100) {
			FATAL("buffered before play \"%s\" is not a positive "
			      "percentage and less than 100 percent, line %i"
			      "\n", param->value, param->line);
		}
	}

	buffered_before_play = (perc / 100) * buffered_chunks;
	if (buffered_before_play > buffered_chunks) {
		buffered_before_play = buffered_chunks;
	} else if (buffered_before_play < 0)
		buffered_before_play = 0;

	allocationSize = buffered_chunks * CHUNK_SIZE;	/*actual buffer */
	allocationSize += buffered_chunks * sizeof(float);	/*for times */
	allocationSize += buffered_chunks * sizeof(mpd_sint16);	/*for chunkSize */
	allocationSize += buffered_chunks * sizeof(mpd_sint16);	/*for bitRate */
	allocationSize += buffered_chunks * sizeof(mpd_sint8);	/*for metaChunk */
	allocationSize += sizeof(PlayerData);	/*for playerData struct */

	/* for audioDeviceStates[] */
	allocationSize += device_array_size;

	if ((shmid = shmget(IPC_PRIVATE, allocationSize, IPC_CREAT | 0600)) < 0)
		FATAL("problems shmget'ing\n");
	if (!(playerData_pd = shmat(shmid, NULL, 0))) 
		FATAL("problems shmat'ing\n");
	if (shmctl(shmid, IPC_RMID, NULL) < 0) 
		FATAL("problems shmctl'ing\n");

	playerData_pd->audioDeviceStates = (mpd_uint8 *)playerData_pd +
	                                    allocationSize - device_array_size;
	buffer = &(playerData_pd->buffer);

	memset(&buffer->convState, 0, sizeof(ConvState));
	buffer->chunks = ((char *)playerData_pd) + sizeof(PlayerData);
	buffer->chunkSize = (mpd_uint16 *) (((char *)buffer->chunks) +
					    buffered_chunks * CHUNK_SIZE);
	buffer->bitRate = (mpd_uint16 *) (((char *)buffer->chunkSize) +
					  buffered_chunks * sizeof(mpd_sint16));
	buffer->metaChunk = (mpd_sint8 *) (((char *)buffer->bitRate) +
					   buffered_chunks *
					   sizeof(mpd_sint16));
	buffer->times =
	    (float *)(((char *)buffer->metaChunk) +
		      buffered_chunks * sizeof(mpd_sint8));
	buffer->acceptMetadata = 0;

	playerData_pd->playerControl.wait = 0;
	playerData_pd->playerControl.stop = 0;
	playerData_pd->playerControl.pause = 0;
	playerData_pd->playerControl.play = 0;
	playerData_pd->playerControl.error = PLAYER_ERROR_NOERROR;
	playerData_pd->playerControl.lockQueue = 0;
	playerData_pd->playerControl.unlockQueue = 0;
	playerData_pd->playerControl.state = PLAYER_STATE_STOP;
	playerData_pd->playerControl.queueState = PLAYER_QUEUE_BLANK;
	playerData_pd->playerControl.queueLockState = PLAYER_QUEUE_UNLOCKED;
	playerData_pd->playerControl.seek = 0;
	playerData_pd->playerControl.closeAudio = 0;
	memset(playerData_pd->playerControl.utf8url, 0, MPD_PATH_MAX);
	memset(playerData_pd->playerControl.erroredUrl, 0, MPD_PATH_MAX);
	memset(playerData_pd->playerControl.currentUrl, 0, MPD_PATH_MAX);
	playerData_pd->playerControl.crossFade = crossfade;
	playerData_pd->playerControl.softwareVolume = 1000;
	playerData_pd->playerControl.totalPlayTime = 0;
	playerData_pd->playerControl.decode_pid = 0;
	playerData_pd->playerControl.metadataState =
	    PLAYER_METADATA_STATE_WRITE;

	playerData_pd->decoderControl.stop = 0;
	playerData_pd->decoderControl.start = 0;
	playerData_pd->decoderControl.state = DECODE_STATE_STOP;
	playerData_pd->decoderControl.seek = 0;
	playerData_pd->decoderControl.error = DECODE_ERROR_NOERROR;
	memset(playerData_pd->decoderControl.utf8url, 0, MPD_PATH_MAX);
}

PlayerData *getPlayerData(void)
{
	return playerData_pd;
}

void freePlayerData(void)
{
	/* We don't want to release this memory until we know our player and
	 * decoder have exited.  Otherwise, their signal handlers will want to
	 * access playerData_pd and we need to keep it available for them */
	waitpid(-1, NULL, 0);
	shmdt(playerData_pd);
}